This invention relates to a mechanism for opening and closing windows and doors.
Many different forms of mechanisms for opening and closing windows in a domestic environment are available, including extendable chain arrangements and mechanical lever arms. Each mechanism has its own inherent advantages and disadvantages which make them suitable for various applications such as window and hinge types. Presently available opening and closing mechanisms for awning and casement windows are primarily of a mechanical linkage type, separate from the mechanical hinge arrangement which couples the window to the frame, and generally comprise a form of lever arm extending from the frame to the window sash. The lever arm may typically be extendable from an orientation generally parallel to the frame (window closed) to an orientation transverse to the frame (window open) by means of a geared coupling from the lever arm to a rotatable handle or the like that is operable by the user.
Embodiments of the present invention aim to provide an opening and closing mechanism for windows and doors which operates by way of a cord or cable, for example, which, when an appropriate tension is applied, causes the window/door to open or close. For closing of the window, for example, the cord or cable tension may be applied directly between the window sash and the frame, and for opening the window the tension may be applied to an arm of the hinge by which the window is mounted to the frame. The mechanism is particularly well adapted for use in casement and awning window fittings.
In accordance with the invention, there is provided a mechanism for hinged opening and closing movement between first and second components wherein the first and second components comprise a window or door and a window or door frame, comprising a runner mounted to the first component, a connecting arm mounted at one end for pivotal movement on a first pivot mounting coupled to the runner, the other end of the connecting arm being adapted for pivotal connection to the second component, an opening cord or cable coupled to exert a tension force between a hinged or pivotal connection of the first and second components and said first pivot mounting substantially along said runner so as to effect a relative movement toward one another along said runner as between said hinged or pivotal connection and said first pivot mounting, a closing cord or cable adapted for connection to said second component for exerting a tension force between said first and second components for angular movement of said first and second components toward one another, and a winding mechanism coupled to the opening and closing cords or cables for applying said respective tension forces to the opening and closing cords or cables.
In accordance with the present invention, there is also provided an opening and closing mechanism for a window or door comprising an elongate frame member, first and second pivot mount members coupled to the frame member towards opposite ends thereof and at least one of the first and second pivot mount members being slidable along the frame member so that the first and second pivot mount members are movable relative to one another, a lever arm having one end pivotally coupled to the first pivot mount member to enable pivotal movement thereof relative to the frame member between a closed position where the lever arm is substantially parallel to the frame member and an open position where the lever arm is transverse to the frame member, a connecting arm having one end pivotally coupled to the second pivot mount member and the other end pivotally coupled at an intermediate portion of the lever arm, an opening cord or cable portion which is coupled to one or both of the first and second pivot mount members for applying a force therebetween to effect relative movement of the first and second pivot mount members toward each other along the frame member for opening of the window or door, a closing cord or cable portion which is coupled between the connecting arm or lever arm and the frame member for applying a force therebetween to effect relative angular movement of the lever arm and connecting arm toward the frame member for closing of the window or door, and a winding mechanism for winding and unwinding the opening and closing cord or cable portions to apply said forces for opening and closing of the window or door, in use.
Preferably the first pivot mount member includes a wedge member positioned to slide along the frame member between the second pivot mount member and a lever arm mounting of the first pivot mount member, and wherein the wedge member is coupled to the opening cord or cable portion and is relatively movable with respect to the lever arm mounting over a limited distance along the frame member. The wedge member may be coupled to the lever arm mounting by way of a tension spring and sliding spring limit arms interconnecting the wedge member and lever arm mounting to limit the separation thereof and thus limit extension of the tension spring. Preferably the wedge member has a wedge surface which, upon relative movement of the first and second pivot mount members toward one another, acts against the end of the connecting arm coupled to the lever arm to force the connecting arm and lever arm angularly out from the frame member.
The winding mechanism preferably includes a rotatable spool upon which the opening and closing cord or cable portions are wound, in use, and wherein the opening and closing cord or cable portions are coupled around the spool such that winding the opening cord or cable portion onto the spool unwinds the closing cord or cable portion therefrom, and vice versa. The opening and/or closing cord or cable portion may be coupled between the winding mechanism and the frame member by way of a cable sheath.
In one form of the invention, the spool includes separate guiding slots for the opening cord or cable portion and the closing cord or cable portion, and wherein each of the opening and closing cord or cable portions have an end portion affixed in relation to the spool. The guiding slot in the spool for the closing cable portion may be formed in a spiral and have a variable winding radius.
The winding mechanism can be provided with a ratchet mechanism which allows rotation of the spool in one direction by application of tension on the opening cable, and prevents rotation of the spool in the other direction upon application of tension on the closing cable. In this case, the driving means may be coupled to the spool by way of a cam action mechanism to disengage said the ratchet mechanism and allow the driving mechanism to drive the spool.
In a particular embodiment of the invention an opening/closing mechanism for opening and/or closing a window comprises a hinge arrangement having a lever arm with a first end pivotally mounted to the window frame with the first pivotal end being slidably movable substantially parallel to the window frame and a second end mounted to the window sash, a rotatable spool, and a flexible cord, cable or the like which has a first end affixed in relation to the window frame, in use, and a second end attached to the second end of the lever arm or to the window sash, wherein the cord, cable or the like passes from the first end to a transition mounting comprising an aperture, roller, pulley or the like mounted for movement with the first end of the lever arm, at least once around the spool, and to the second end attached to the window sash.
Preferably the transition mounting is provided on a slide member which is slidably movable along the same axis as the first end of the lever arm, and is attached said first end by way of a tension spring. Preferably extension of the tension spring is limited to a predetermined length by a limiting means such as a fixed length cord or cable, or a pair of arms having respective interfitting slot and lug formations which are relatively slidable to a fixed extent.
In a preferred form of the invention, the mechanism includes an elongate runner frame which, in use, is mounted along the window frame, with the lever arm arranged to extend along an edge of the window sash, in use. The runner frame preferably has a track along which the first end of the lever arm, and the slide member, are slidably movable. With the mechanism in a xe2x80x9cclosed windowxe2x80x9d configuration the lever arm extends generally parallel to the runner frame and first end of the lever arm is disposed to a first end of the runner frame, with the rotatable spool mounted at the other, second end of the runner frame. In this configuration the second end of the lever arm is disposed adjacent the spool. The slide member having the cord transition mounting is disposed along the runner frame between the lever arm first end and the spool. A connecting arm is preferably provided having a first end pivotally connected to the runner frame between the first and second ends thereof, and a second end pivotally connected intermediate the first and second ends of the lever arm. The slide member is preferably formed with an angled wedge portion which, upon initial movement of the slide member from the xe2x80x9cclosed windowxe2x80x9d configuration of the mechanism, is forced between the track of the runner frame and the second end of the connecting arm so as to force the connecting arm and lever arm transversely outward from the runner frame.
The spool and the first end of the connecting arm may alternatively be mounted to a frame block which is detachably coupled to the runner frame at the second end thereof. This arrangement facilitates attachment and detachment of the spool and connecting arm to/from the runner frame in a single unit, which allows the slide member and lever arm to also be coupled and decoupled to/from the runner frame track towards the second end thereof, which in turn enables easier mounting of the lever arm to the window sash and the runner frame to the window frame during installation as well as removal of the window sash from the frame for maintenance or the like.
The slide member may act upon the second end of the connecting arm as mentioned above, but may alternatively or additional act upon a lug or the like which extends from the connecting arm or even from the lever arm itself. In this way the distance from the pivot points of the connecting and lever arms can be tailored to provide a suitable force upon the arms for movement thereof upon a suitable force being applied to the slide member according to the angle of the wedge portion. Furthermore, a plurality of slide members may be utilised in some applications, acting at separate points along the connecting arm and/or lever arm to provide the required pivotal movement of the arms outwardly from the runner frame at the beginning of the hinge movement.